Ball a has half the mass and eight times the kinetic energy of ball
b. what is the speed ratio va / vb ?

Explanation :

It is given that there are two balls a and b. Ball a has half the mass of ball b. The kinetic energy of ball a is eight times the kinetic energy of ball b.

We know that the kinetic energy of an object is given by :

Taking ratios of kinetic energy of both balls a and b.

So,

Hence, this is the required solution.                          

i dont think you are wrong for wanting to get even with someone who did you wrong.

(i'm an eye for an eye kind of person) but if this person hurt you in a sexual way, i dont suggest doing anything to him. he should be taken to the proper authorities, you could go to jail depending on what you do. if it was something small like your sibling took your spot on the couch, than yea, i would get even with him by taking one of his favorite snacks lol. but i dont suggest you doing anything illegal.

force is mass*acceleration.

we have a very small mass: 11.4*0.001 kg

if we want 0.035n of force, we need an acceleration:

0.035 = 11.4*0.001*a

a = 0.035/(11.4*0.001) m/s^2